From Natural Tree Forks to Grid Shells: Towards a Self-forming Geometry

Abstract

Forest thinning generates a lot of “waste” in the form of irregular tree branches. Their unpredictable shape and properties are a challenge for the construction industry; however, this research sees this as an opportunity and proposes a novel way to utilise them as structural members of grid shells suited for shelters, roofs, etc. The properties of trees at micro-level informed the generation process. There, chains of cellulose and hemicellulose bundle together to form microfibrils, that on the other hand are the building blocks of tree cells. Peculiar observation is the fact that microfibrils possess self-assembling power that allows them to form structures by themselves resulting in geometry and form with a specific pattern, as a function of the forces at the micro-level. There, reducing the free energy of the surfaces is of paramount importance to ensure form stability. In attempt to correlate to, but not imitate this process, the author proposes rules for morphogenesis based on reciprocal connections that allow the branches to self-form structures based on their original unmodified shape and properties, thus creating geometry from the available material. Architects and engineers can interfere in this assembly process by setting higher level conditions that guide the result but never define it explicitly.